Lattice misfit versus performance of thin film electroluminescent structures

Tools

Mastio, E.A., Cranton, W.M. ORCID: 0000-0002-0142-7810 and Thomas, C.B., 2001. Lattice misfit versus performance of thin film electroluminescent structures. Journal of Applied Physics, 89 (3), pp. 1605-1611. ISSN 0021-8979

Preview

Text
196298_290 Cranton Publisher.pdf
Download (100kB) | Preview

Official URL: http://dx.doi.org/10.1063/1.1335646

Abstract

Thin polycrystalline electroluminescent thin films (TFEL) of ZnS:Mn (phosphor) and Y2O3 (insulator) were deposited individually or as multilayers onto Si (100) substrates. Their crystallinity and the luminescent efficiency of the phosphor films were investigated at varying thermal annealing temperatures. It is shown that the luminescent quality of the phosphor layer increases up to 700 °C, whereas the electroluminescence operating intensity of TFEL devices saturates at 500 °C. The structural analysis of the insulating and phosphor layers shows that they recrystallize at annealing temperatures of, respectively, 500 and 600 °C, and that their lattice misfit doubles at processing temperatures >=500 °C. Since TFEL devices should benefit from enhanced luminescence efficiency and crystallinity at high annealing temperatures, we suggest that the lack of improvement in device performance beyond 500 °C is due to interface alterations. According to previous works, we propose that the lattice misfit increase between the phosphor and dielectric thin films modifies the morphology of the phosphor–insulator boundary inducing a modification of the interface states density, and hence, modifying high field electron transport properties of TFEL devices.

Item Type:

Journal article

Publication Title:

Journal of Applied Physics

Creators:

Mastio, E.A., Cranton, W.M. and Thomas, C.B.

Publisher:

American Institute of Physics

Place of Publication:

Melville, NY

Date:

2001